Trainer uses Jack Daniels' VDOT system. VDOT is a fitness score worked out from a recent race or hard run (see Fitness and VDOT), and each training zone is a pace derived from it. Plans name a zone ("at T pace") rather than a number, and the app shows your pace for that zone beside each session. As your fitness changes, the paces change with it.
The zones
Easy (E)
Builds your aerobic base: more capillaries, more mitochondria, and tougher muscles, tendons and bones. It's also how you recover between hard days. It should feel conversational, and most of your running happens here.
Marathon (M)
Race-specific endurance for the marathon, and a chance to practise fuelling. It feels steady and controlled.
Threshold (T)
Raises your lactate threshold, so you can hold a faster pace for longer. It feels "comfortably hard": a pace you could race for about an hour.
Interval (I)
Develops your VO2max, the ceiling on how much oxygen you can use. It's hard, run in bouts of 3–5 minutes.
Repetition (R)
Builds speed, running economy and form. It's fast but relaxed, with full recovery between reps.
Daniels' limits on quality per session
From Daniels' Running Formula:
- T: the total at T pace in one session is about 10% of weekly distance. It can be one continuous tempo run of about 20 minutes, or "cruise intervals" (for example 3–5 × 1.6 km with 1 minute rest).
- I: the lesser of 10 km and 8% of weekly distance per session. Each work bout lasts 3–5 minutes, with jog recoveries about as long as the bout or slightly shorter.
- R: the lesser of 8 km and 5% of weekly distance per session. Reps are usually 200–400 m with full recovery (a jog of the same distance or longer).
- Long run: about 25–30% of weekly distance, at E pace.
Hard ("quality") sessions should be separated by at least one easy day or rest day.
Strides
Strides are 15–20 second relaxed accelerations to about R pace, with full walk or jog recovery. They're added to the end of easy runs 1–2 times a week. They build speed and form without adding fatigue, which suits beginners and low-volume runners for whom full R sessions would be too much. They don't count as hard running.
Goal pace work
When you have a goal pace (for example 4:40/km for 10 km), sessions at that pace teach rhythm and confidence. Keep them to a modest share of the week, and build them up gradually. Examples:
- 4 × 1 km at goal pace.
- 3 × 2 km at goal pace.
- Later, 2 × 3 km at goal pace.
If the goal pace is much faster than your current T pace, the goal is ambitious. Goal pace work should then be short reps, and most quality should stay at T and I pace from current fitness.
How Trainer applies it
- Every session is easy, a long run, or a session in one zone: threshold, intervals, repetition, marathon pace or goal pace. Races and time trials are their own type.
- A long run is at E pace. It may finish with a few kilometres at goal pace when your goal has a target time, and at M pace otherwise.
- "Hard distance" means the part of a session at M pace or faster, not counting warm-up and cool-down. Easy runs and strides have none.
- Hard sessions, including races, never fall on consecutive days, including Sunday into Monday.
Sources
- Daniels J. Daniels' Running Formula. 3rd ed. Human Kinetics; 2014.
- Trainer's VDOT calculations are tested against that book's Tables 3.1 and 3.2.